The age that kids start school in Australia varies according to state, but generally once kids turn six, they must attend an institution. In some states kids can start school once they turn five, but they are not required to by law, according to KidSpot.
In Victoria and the Australia Capital Territory, children must have turned five years old before April 30 in order to start the school year. Those children who turn five after that date must wait until the following school year. The law is similar in Queensland, where children who turn five before June 30 enter a year of prep, before beginning their first year of school the following year.